Non-saxophone players look away now ...
I'm a tenor player through and through, and a proud owner of a P. Mauriat PMXT-66R. I genuinely think its the best horn I've ever player, with a full, warm tone, even intonation and very playable mechanism.
On the end of that, I put a 7* Otto Link Tone Master which gives me as much or as little bite as I need, whilst not overshadowing the character of my horn. A new mouthpiece is always the first place to look if you're after an upgrade as its potentially a lot cheaper than a new horn and makes a really surprising difference to your sound on the instrument.
I also think players often overlook the impact that their ligature has on the overall tone and playability of their horn, and I've used Francois Louis ligs on all my saxes for years. Regardless of what setup you use, a Francois Louis ligature just seems to give you more of whatever it was that you already liked about it!
I've used Rico Select Jazz 3S filed reeds ever since my old teacher gave me one. I've never really experimented with much else as I just haven't needed to! I find them bright enough to punch through in a loud band setting whilst also subtle enough for intimate gigs and recording sessions. And they're almost always consistent, straight out of the box.
Having said all that, there's absolutely no amount of money you can spend that will improve your sound more than practice! Long tones, harmonics, dynamic exercises, articulation patterns and slurred intervals are by far the cheapest way to sound your best. The way I see it, me and my instrument are a team and we'll always be held back by the weakest factor. If you really are convinced that your horn is limiting your playing then go buy something better ... but more often than not I find it to be the other way around! Its like dieting and exercise versus the latest internet-craze miracle pill ... there's no quick fixes here people!
And finally ...
As a multi-instrumentalist, I also play Trevor James saxes with ebonite Otto Link and Selmer mouthpieces, a Buffet Clarinet with a Rico mouthpiece, BG France ligature and Mitchell Lurie reeds and a Yamaha Flute.